Mixing apparatus



Sept. 18,1923. 1,468,226

H. C. COLBURN ET AL MIXING APPARATUS Filed Jan; 3, 1919 INVENTORS H6. COLBURN AND 5 A. COLBURN.

Patented Sept. "18, 1923.

UNITED [STATES- PATENT OFFICE,

HERBERT C. COLBURN AND ERNEST COLBURN, OF DENVER, COLORADO, ASSIGNOBS TO THE COLBURN FLOTATION & ENGINEERING COMPANY, OF DENVER, COLORADO,

- A CORPORATION.

- MIXING APPARATUS.

Application filed January 8, 1919. Serial No. 269,518.

To all whom it may concern:

Be it known that we, HERBERT C. C01.- BURN and ERNEST A. Consume, citizensof the United States, residing at Denver, in

6 the county of Denver and State of Colorado,

have invented certain new and useful Improvements in Mixing Apparatus, of which the following is a specification.

This invention relates to apparatus for 1D the separation of ores by flotation and more particularly to apparatus for performing an ore-separating process which, briefly, con,- sists in first mixing and securing ore-pulp under a partial vacuum and then admitting the same beneath the surface of a liquid in a settling vessel which has means for causing the entering material to separate into two classes, namely the bared and polished metallic particles which ascend to the surface of the liquid and the water-wetted silicious gangue which settles to the bottom of the vessel.

The gangue is discharged through an outlet which may be connected with the mixing element of a second similar-apparatus,

for retreatment, and thevalues which congregate at the surface of the liquid in a froth or thin coating are removed across an overflow.

The settling vessel has been made the subject of a separate application for patent, Serial No. 269,517 filed January 3, 1919, granted May 9, 1922, Patent No. 1,415,314

which. relates primarily to the element which ccomplishes themixing and scouring actions of the process.

In the accompanying drawings in the various views of which like parts are similarly designated, We have shown an embodiment of our invention in the best form at present known to us,

Figure 1 representing a sectional elevation of the apparatus;

Figure 2, a section on the line 22; Figure 1, looking in the direction of the arrow A, .and

Figure 3, a fragmentary section along the same line looking in the op osite direction as indicated by the arrow The settling vessel of the apparatus, designated by the reference numeral 2 in F ig-' ure 1, consists of a spitzkasten which in one of its sides has a slot-shaped intake opening 3 and; opposite thereto a slanting deflecting surface 4.

An adjustable battle 5 extends over the opening to cause entering material to move in a downwardly directed current toward the surface 4, an outlet 6 at the bottom of v the vessel is provided for the discharge of the settlin gangue and an overflow 7 at the top 0 the vessel serves to remove the supernatant film of metallic particles'ofi the surface of the liquid. g

The mixing element of the a-ppartus consists of a partially circular caslng 8 ta rthe slot-shaped inletconduit 13 is connected either with a source of supply of fresh material or with the outlet opening at the bottom of a. settling vessel of a similar apparatus.

A vertically extending pipe 14 preferably provided with a cup-shaped mouth 15, connects with an opening in the wall of the neck 12 to admit air, oil or other fluid to the interior of the casin and it is rovided with a hand-adjusted valve 16 w ich controls the quantity of fluid or fluids admitted to the casing during a determinate period of operation.

A. mixing contrivance within the casing consists of two similarly formed members which are placed oppositely in axial alinement to cooperatively scour and agitate the pulpous matter which enters the casing through its inlet opening at the inner end of the neck.

Each of the members of the contrivance consists of a cylindrical rim .17 and a plurality of blades 18 extending radially inwardly therefrom.

One of the members 19 is formed integrally with a wall of the casing, concentric with the inlet openin in said wall, and the other member 20 is mounted upon the end of a shaft 21 which extends through a stulfing-box 22 on the opposite wall of the casing.

The shaft is rotatabl supported in a pillow-box on a standar 23 erected upon a base 24 upon which the-casing 8 is sup rted and it carries between this standar and the stufling box, a pulley 25 for its operative connection with motor or'other convenient source of power.

The outer end of the shaft is threaded for the application of a pair of nuts 26 which bear upon a thrust-washer 27 placed in engagement with the outer end of the pillow-box.

The nuts are secured inst displacement by a set-screw 28 and it is their purpose in addition to receivin the end thrust of the shaft, to regulate t e distance between the two members of the mixing contrivance within the casing.

The casing has in its bottom, an opening which is normally closed by a removable plug 29 and is used for the drainage of matter when the machine is brought to a condition of rest after a period of operation.

The intake-opening 30 of the casing is of smaller area than the outlet opening of the same at the base of the tapering nozzle 9, so that during the rotary movement of the member 20, a partial vacuum is formed in the casing which causes the dissemination or air contained in the material and which disrupts colloidal envelopes of the metallic particles of the same whereby to facllitate their disruption by the scouring action of the cooperative members of the apparatus.

A proportion of 1 to 4 between the area of the inlet opening of the casing and that of the discharge openin of the same appears to be well suited %or the purpose of creating the desired degree of vacuum within the agitation chamber of the mixlng element.

In the operation of the apparatus, the shaft is rotated at a velocity which affects a displacement of material in the casing exceeding the capacity of the inlet, and the partial vacuum in conse uence created in the casing, is regulated by t e distance between the two members of the agitator which scour and agitate the material until in a thoroughly intermixed condition it is discharged through the nozzle which connects with the intake opening of the settling vessel.

After the colloidal envelopes of the metallic particles in the material are expanded by the partial vacuum constantly maintained in the casing, they are smoothed and polished between the members of the mixing contrivance, with the result that they repel the water in the pulp and acquire an aflinity for the oil or other contaminating agent supplied to the material either before it enters the casing 01 after it is admitted to the settling vessel.

The air naturally contained in the material and that admitted through the pipe. 14 is at the same time finely disseminated throughout the agitated mass and the worthless silicious constituents of the pulp are saturated with moisture.

When the material in this condition enters froth or film which is removed across the v It will be observed that owing to the central position of the nozzle of the mixing element of the apparatus as herein described the material is agitated and intermixed without any pumping action and that the moving member of the agitator may be rotated in either direction with equal efiect.

Having thus described the apparatus in the best form at present known to us, we desire it understood that variations in the construction, proportions and arrangement of its parts may be resorted to within the spirit of our invention as defined in the following claims.

We claim- 1. A mixing apparatus comprising a chamber and within the same, oppositely spaced stationary and rotary agitating members, each composed of a cylindrical rim and blades extending radially inward from the rim and of substantially the same depth. 2. A mixing apparatus comprising a chamber, a stationary agitator member therein, a longitudinally movable rotary shaft extending into said chamber, a rotary agitating member on said shaft opposite said stationary agitating member, each of said agitating members having a cylindrical rim and radial blades extending radially inward from the rims and of substantially the same depth, and means for adjusting the shaft and the rotary agitating member relatively to said stationary agitating member.

3. In an ore treating apparatus, a chamber having a single inlet and an outlet of a larger area than said inlet, and an agitating and mixing element within said chamber comprising stationary and rotary elements, each having radial blades and cylindrical rims, the outlet being positioned relative to said element and said inlet to produce, by reason of its larger area, a partial vacuum in the chamber when the ele ment is in operation.

4. In an ore treating apparatus, a chamber having an inlet and an outlet of a larger area than said inlet, an agitating and mixing element within said chamber comprisstationary and rotary elements, each having stationary and rotary elements, each ing radial'blades and cylindrical rims, and having radial blades and cylindrical rims, means for feeding material to the chamber and means for introducing air to the mathrough the inlet at a rate below the disterial at its point of entrance through said placing capacity of agitating and mixing 1 inlet. element.

5. In an ore treating apparatus, a cham- In testimony whereof we have affixed our her having an inlet and an outlet of a larger signatures. area than said inlet, an agitating and m1x- HERBERT C. COLBURN.

ing element within said chamber comprising ERNEST A. COLBUR-N, 

